Wireless Temperatures around the house
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Posts: 46,084
If you only need locally settable thermostatic action
rather than spread of temp readings just have a common
thermostat [noparse][[/noparse]passive or fancy with battery operated timer]
turn a transmitter [noparse][[/noparse]like rentron sells - laipac.com] on
with a location coded signal every so often or on change
of thermostat contacts.
If you want "continuous" temperature data use two 555 cmos
units and an RF transmitter - one 555 has a thermistor
to modulate its tone which modulates the transmitter and
the other 555 turns on the transmitter for a short
duty cycle. Assuming the 2nd 555s are not synchronized
with each other and are short tone bursts will be received
without colliding a lot of the time and you can pick
off the corresponding temperature of that unit with
appropriate filters - and feed them to a BSII using pulsin
to get temperature. Use a reasonably time & temp stable
timing capacitor with the 555.
Issues are: 555 + thermistor stability - quite good in this
application; _not_ having interfering signals from more than
one transmitter on at a time - a bit harder as the number of
transmitters increases.
Don't forget to program "anticipator" function into your program.
It takes a while for heat input into a room to affect the
thermostat - whatever it's nature - so you need to turn off
before you think you've arrived at the right heat or you'll
overheat and then have a long cool down period.
You also should look for at least two consecutive consistent
readings before changing heat input to make sure you don't have
a transmitter collision artifact.
Usually you want to be able to have a person in a room signal
an up or down temperature change so the first suggestion made -
using a standard mechanical thermostat and transmitter - may
be most relevant.
A BSII sorting the received signals out would be an interesting
stamp project....
>>>
Date: Thu, 01 Mar 2001 14:22:38 -0000
From: Christopher_Hill@M...
I'm looking for anything that can send a wireless temperature related
signal, be it digital or analogue, (can be calibrated or converted to
temperature reading at reciever by STAMP) to a central reciever that
can understand recieving several temperatures from different
transmitters.
Example
Many Transmitters sending say a resistance related signal and a Room
code to a Central Reciever that can sort the Room Signals out and
convert the Resistance to Degrees.
Must be cheap <$10 per room temperature ?
Any pointers would be greatful
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rather than spread of temp readings just have a common
thermostat [noparse][[/noparse]passive or fancy with battery operated timer]
turn a transmitter [noparse][[/noparse]like rentron sells - laipac.com] on
with a location coded signal every so often or on change
of thermostat contacts.
If you want "continuous" temperature data use two 555 cmos
units and an RF transmitter - one 555 has a thermistor
to modulate its tone which modulates the transmitter and
the other 555 turns on the transmitter for a short
duty cycle. Assuming the 2nd 555s are not synchronized
with each other and are short tone bursts will be received
without colliding a lot of the time and you can pick
off the corresponding temperature of that unit with
appropriate filters - and feed them to a BSII using pulsin
to get temperature. Use a reasonably time & temp stable
timing capacitor with the 555.
Issues are: 555 + thermistor stability - quite good in this
application; _not_ having interfering signals from more than
one transmitter on at a time - a bit harder as the number of
transmitters increases.
Don't forget to program "anticipator" function into your program.
It takes a while for heat input into a room to affect the
thermostat - whatever it's nature - so you need to turn off
before you think you've arrived at the right heat or you'll
overheat and then have a long cool down period.
You also should look for at least two consecutive consistent
readings before changing heat input to make sure you don't have
a transmitter collision artifact.
Usually you want to be able to have a person in a room signal
an up or down temperature change so the first suggestion made -
using a standard mechanical thermostat and transmitter - may
be most relevant.
A BSII sorting the received signals out would be an interesting
stamp project....
>>>
Date: Thu, 01 Mar 2001 14:22:38 -0000
From: Christopher_Hill@M...
I'm looking for anything that can send a wireless temperature related
signal, be it digital or analogue, (can be calibrated or converted to
temperature reading at reciever by STAMP) to a central reciever that
can understand recieving several temperatures from different
transmitters.
Example
Many Transmitters sending say a resistance related signal and a Room
code to a Central Reciever that can sort the Room Signals out and
convert the Resistance to Degrees.
Must be cheap <$10 per room temperature ?
Any pointers would be greatful
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today! For your FREE software, visit:
http://dl.www.juno.com/get/tagj.